People 50 years of age and older with macular degeneration and visual acuity worse than 20/50 in the study eye and the same or better vision in the other eye may be eligible for this study. Candidates will undergo fluorescein angiography to try to locate feeder vessels. For this procedure, a yellow dye is injected into an arm vein. The dye travels to the blood vessels in the eyes, and pictures of the retina are taken using a camera that flashes a blue light into the eye. The pictures show if any dye has leaked from the vessels into the retina, indicating possible blood vessel abnormality.